Client Need
The City of Phoenix selected the design team of Green Mountain Technologies and AW Architects in August of 2014 to design the new Phoenix Compost Facility project.
Approximately 50% of the material in the waste stream of the adjacent transfer station is biodegradable and potentially eligible for composting at the new facility. Composting could achieve a significant amount of material diversion from the city landfill and a large reduction in hauling costs to the City of Phoenix. The facility is also seen as a magnet for attracting other integrated technologies to the Resource Innovation Campus (RIC) master plan for greater waste diversion.
GMT’s Solution
GMT proposed using a cutting-edge approach to composting by developing mass turned aerated pads with reversing air flow management. This concept allows municipal compost projects to process large amounts of compost while minimizing footprint, water and energy usage. The biggest challenge was coming up with systems to irrigate and cool the compost piles in the hot desert climate.
The capacity of this system was developed in phases, this first phase was for 55,000 TPY, and implemented for $12.5 million including all required infrastructure, plus processing equipment, the second phase will expand the facility to 110,000 TPY as shown in the drawing above, and the final site capacity 220,000 TPY by expanding directly to the east from the second phase, and adding shade canopies where customers unload.
Client Need
Olympic Organics is an ASP composting facility processing up to 20,000 tons per year of food and yard waste in Hansville, WA. The facility currently has 5 bays each 35’ wide and 55’ long and each bay handles 600 cubic yards of mixed green and food waste. Jeff West, the owner of Olympic Organics needed an automatic aeration control system that would control blowers and record temperatures while allowing off-site access to data and controls to reduce his labor costs. The goal was to automate his system so an operator would not have make daily adjustments to blower timers and take temperatures or go to the site on weekends to record data.
GMT’s Solution
In 2014, Green Mountain Technologies installed 5 zone WebMACS controller for the composting facility. The system replaced the cycle timers and connected directly to the existing motor contactors to start and stop blowers. The WebMACS stores up to 16,000 temperature samples per zone and is accessed by the operator’s smart phone while in the loader or anywhere on-site. The system sends out email and text alarms when the temperatures are too high or too low. Once Olympic Organics has internet access at the controller, the WebMACS can be accessed through the internet connection by computer that has the secure log-in password.
The cost of the WebMACS control system was less than $10,000 and installation and training took less than two days. The WebMACS System has saved 1-2 hours of record keeping per day as well as weekend overtime and Jeff estimates that the payback for the WebMACS System will be less than one year.
Client Need
Green Mountain Technologies installed a 12,000 ton per year Aerated Static Pile (ASP) composting system for Washington State University (WSU) in 2007. The facility takes in agricultural waste from the research farms and food waste from the campus. The finished compost is used for sterile bedding and landscaping. The pad is divided into 8 zones, each 15×90’ with 300 cubic yards of compost on each zone.
After eight years of successful composting with their ASP system, the school decided to expand their operation to accommodate an increase in capacity and to also add a zone exclusively for mortality composting.
GMT’s Solution
In 2015, GMT expanded the existing ASP manifold and control system, adding an additional 4 zones to increase capacity and add a zone exclusively for mortality composting.
The ASP process requires no turning and less land area than windrows. The feedstocks are blended in a stationary mixer and water added to create a compostable mix prior to loading on the ASP pad. Then the material is stacked on top of perforated pipe sucks air down through the pile to maintain aerobic conditions and blown through a biofilter to minimize odors. Air flow is regulated by computer controller and dampers to maintain sterilizing temperatures. The cost of the ASP equipment was less than $200,000 and was installed in 3 days.
Client Need
EnviroSmart Composting Facility in Delta, BC had been composting for 15 years using ASP and static pile composting systems. They needed to expand their capacity and increase the rate of composting to handle the increasing food waste stream from the Metro Vancouver area. EnviroSmart receives a variety of other feedstocks from stables, ag processors, landscapers and wood by products. Daryl Goodwin, owner of EnviroSmart was looking for a company that could both design and provide aeration equipment for the facility upgrade.
GMT’s Solution
Green Mountain Technologies was hired to do a preliminary facility evaluation and make recommendations based the existing equipment and land area available. GMT recommended a Turned Aerated Pile (TAP) system with reversing aeration to reduce their processing time and produce a higher quality compost. The 200×200 aerated concrete pad was housed inside a roof structure to keep out the winter weather. The piles are mass bed design which eliminates access lanes and maximizes the footprint of the building. Two 100 hp blowers connect to stainless steel manifolds which distribute the air to sixteen 25’x100’ zones on the air floor. The new building started operation in January of 2015.
Client Need
Vision Recycling operates a network of grinding and composting operations in the Bay area of California. Trucking between drop off/grinding operations and composting sites was becoming more inefficient due to increased traffic and they needed to expand their capacity. Vision decided to develop a new ASP composting pad on an old gravel pit adjacent to their Livermore site. Storm water regulations and the cost of concrete made it impractical to pour a large concrete pad and Vision did not want to use pipe on grade due to labor costs.
GMT’s Solution
GMT designed a low-cost alternative for below grade aeration using concrete beams instead of a continuous concrete pad to
house the aeration piping. Each beam has nozzles imbedded just below the surface to deliver high pressure air into the compost. Vision used recycled crushed concrete to fill in between each beam to create a low-cost solid working surface. The 6 zone system is powered by two high pressure blowers with zone dampers and VFD’s all controlled by GMT WebMACs controller. In all, the site can compost up to 40,000 tons per year on less than 2 acres of working area.
Client Need
Salinas Valley, California is one of the largest agricultural regions in the United States, producing 80% of the nation’s salad greens, 48% of broccoli, 30% of spinach, and 28% of strawberries.¹ With farmers required to overproduce crops to manage supply chains and pathogen scares, Salinas Valley Solid Waste Authority (SVSWA) estimated that 66,700 tons of food waste was brought to Johnson Canyon landfill in 2019 (one of three landfills in the area), resulting in 1/3 of waste derived from organic sources. In addition, California Senate Bill 1383 requires reduction of organic waste in landfills and SVSWA needed to find an affordable way to divert their organic waste from their landfill.
GMT’s Solution
To divert organic waste from SWSWA’s landfill, Green Mountain Technologies (GMT) designed and constructed an ASP composting system within SVSWA’s $2 million dollar budget.
To reduce costs, GMT modified the design to complete the facility without a concrete aeration pad and installed the aeration system in native ground. The aeration system comprises four blowers and is computer controlled. It includes a below grade aeration pad and a pressure vault with cleanouts to maintain the aeration system. The system has high and low aeration zones, and compost is turned and watered every 14 days. The facility also contains an on-site Scott’s T-3 Separator to separate package good products so that maximum diversion of packaged products is possible.
This facility will last SVSWA 25+ years, compared to a neighboring landfill that costed 5 million dollars and will only last 5 years. This model can serve as a blueprint for other cities, counties, and states around the nation that have similar goals of transforming their waste systems to create a circular economy. GMT is also providing ongoing operations support and consulting for meeting the SB1383 requirements for California.
